Re: [Qemu-devel] Virtual Machine Generation ID

[Igor Mammedov <imammedo@redhat.com>]

On Tue, 4 Oct 2016 15:51:40 -0700
Ed Swierk <eswierk@skyportsystems.com> wrote:

> On Thu, Sep 15, 2016 at 5:36 PM, Michael S. Tsirkin <mst@redhat.com> wrote:
> > On Thu, Sep 15, 2016 at 05:23:28PM -0700, Ed Swierk wrote:  
> >> I'm wondering what it will take to finish up work on vmgenid.
> >>
> >> https://lists.gnu.org/archive/html/qemu-devel/2016-01/msg05599.html  
> >
> > We have ACPI_BUILD_TPMLOG_FILE in tree now and I think it could be
> > allocated in a similar way.
> > Integrate patch "fw-cfg: support writeable blobs" to communicate the
> > allocated address back to QEMU.  
> 
> Starting with Igor's last version at
> https://github.com/imammedo/qemu/commits/vmgen_wip , it's not clear to
> me which changes need to be ported, which changes are obsoleted by
> your new fw-cfg stuff and/or upstream churn in ACPI, device
> properties, etc. In particular ACPI is still a total mystery to me,
> though passing a single address from guest to host can't be that hard,
> can it?
> 
> Any clues would be appreciated.
> 
> --Ed

Eventually DMA method for allocating qemu<->guest memory prevailed
so you could use following commits as reference:

f7df22d nvdimm acpi: emulate dsm method
18c440e nvdimm acpi: let qemu handle _DSM method
b995141 nvdimm acpi: introduce patched dsm memory
5fe7938 nvdimm acpi: initialize the resource used by NVDIMM ACPI